Climate and what. Earth's climate. Climate-forming factors on Earth. temperate climate zone

Climate (other Greekκλίμα (genus p. κλίματος) - slope) - long-term regime weather, characteristic of the area due to its geographical provisions.

Climate is a statistical ensemble of states through which a system passes: hydrosphere → lithosphere → atmosphere for several decades. Climate is usually understood as the average value weather over a long period of time (of the order of several decades), that is, the climate is the average weather. Thus, the weather is an instantaneous state of some characteristics ( temperature, humidity, Atmosphere pressure). Weather deviation from the climatic norm cannot be considered as climate change, for example, very cold winter does not speak of a cooling of the climate. Significant evidence is needed to detect climate change trend characteristics atmosphere over a long period of time of the order of ten years. The main global geophysical cyclical processes that shape climatic conditions on Earth, are heat circulation, moisture circulation and general atmospheric circulation.

In addition to the general concept of "climate", there are the following concepts:

free atmosphere climate - studied by aeroclimatology.

Microclimate

macroclimate- the climate of planetary scale territories.

Surface air climate

local climate

soil climate

phytoclimate- plant climate

urban climate

Climate is studied by science climatology. Climate change in the past studies paleoclimatology.

In addition to the Earth, the concept of "climate" can refer to other celestial bodies ( planets, their satellites And asteroids) having an atmosphere.

Climatic zones and climate types vary significantly in latitude, ranging from the equatorial zone to the polar zone, but climatic zones are not the only factor, also important influence rendered by the proximity of the sea, the atmospheric circulation system and the height above sea level. The concepts should not be confused climate zone" And " natural area».

IN Russia and on the territory of the former USSR used classification of climate types created in 1956 famous Soviet climatologist B. P. Alisov. This classification takes into account the features of atmospheric circulation. According to this classification, four main climatic zones are distinguished for each hemisphere of the Earth: equatorial, tropical, temperate and polar (in the northern hemisphere - arctic, in the southern hemisphere - antarctic). Between the main zones are transitional belts- subequatorial belt, subtropical, subpolar (subarctic and subantarctic). In these climatic zones, in accordance with the prevailing circulation of air masses, four types of climate can be distinguished: continental, oceanic, the climate of the western and the climate of the eastern coasts.

Köppen climate classification

equatorial belt

• equatorial climate- a climate where winds are weak, temperature fluctuations are small (24-28 ° C at sea level), and precipitation is very plentiful (from 1.5 thousand to 5 thousand mm per year) and falls evenly throughout the year.

subequatorial belt

• Tropical monsoon climate- here in summer instead of the eastern trade wind between the tropics and the equator there is a western air transport (summer monsoon), which brings most of the precipitation. On average, they fall almost as much as in the equatorial climate. On the slopes of the mountains facing the summer monsoon, precipitation is the greatest for the respective regions, the warmest month, as a rule, occurs immediately before the onset of the summer monsoon. It is typical for some areas of the tropics (Equatorial Africa, South and Southeast Asia, Northern Australia). East Africa and Southwest Asia also have the highest average annual temperatures on Earth (30-32 °C).

  Monsoon climate on tropical plateaus

tropical belt

• Tropical dry climate

  Tropical humid climate

subtropical belt

• mediterranean climate

  Subtropical continental climate

  Subtropical monsoon climate

  Climate of high subtropical highlands

  Subtropical climate of the oceans

Temperate zone

• temperate maritime climate

  temperate continental climate

  temperate continental climate

  Moderate sharply continental climate

  temperate monsoon climate

subpolar belt

• subarctic climate

  subantarctic climate

Polar belt: polar climate

• arctic climate

  Antarctic climate

Widespread in the world climate classification, proposed by the Russian scientist W. Köppen(1846-1940). It is based on the mode temperature and degree of moisture. According to this classification, eight climatic zones with eleven types of climate are distinguished. Each type has exact value parameters temperature, the number of winter and summer precipitation.. Many types of climates according to the Köppen climate classification are known by names associated with the vegetation characteristic of this type.

also in climatology The following concepts related to climate characteristics are used:

continental climate- “climate, which is formed under the influence of large land masses on the atmosphere; distributed in the interior of the continents. It is characterized by large daily and annual air temperature amplitudes.

maritime climate- “climate, which is formed under the influence of oceanic spaces on the atmosphere. It is most pronounced over the oceans, but also extends to areas of the continents that are subject to frequent impacts of marine air masses.»

mountain climates- "Climatic conditions in mountainous areas." The main reason for the difference between the climate of the mountains and the climate of the plains is the increase in altitude. In addition, important features are created by the nature of the terrain (degree of dissection, relative height and direction of mountain ranges, exposure of slopes, width and orientation of valleys), glaciers and firn fields exert their influence. A distinction is made between the actual mountain climate at altitudes less than 3000-4000 m and the alpine climate at high altitudes.

Arid climate- “climate of deserts and semi-deserts”. Large daily and annual air temperature amplitudes are observed here; almost complete absence or insignificant amount of precipitation (100-150 mm per year). The resulting moisture evaporates very quickly.

Humid climate- a climate with excessive moisture, in which solar heat enters in quantities insufficient to evaporate all the moisture coming in the form of precipitation

Nival climate- "a climate where there is more solid precipitation than can melt and evaporate." As a result, glaciers are formed and snowfields are preserved.

solar climate(radiative climate) - theoretically calculated intake and distribution over the globe solar radiation (excluding local climate-forming factors

Monsoon climate- a climate in which the cause of the change of seasons is a change in direction monsoon. As a rule, during the monsoon climate, summers are abundant in precipitation and winters are very dry. Only in the eastern part of the Mediterranean, where the summer direction of the monsoons is from land, and the winter direction is from the sea, the main amount of precipitation falls in winter.

trade wind climate

Brief description of the climates of Russia:

Arctic: January t −24…-30, summer t +2…+5. Precipitation - 200-300 mm.

Subarctic: (up to 60 degrees N). summer t +4…+12. Precipitation - 200-400 mm.

Climate is a long-term weather regime characteristic of a given area due to its geographical location.

Climate is a statistical ensemble of states through which the system passes: hydrosphere → lithosphere → atmosphere over several decades. By climate it is customary to understand the average value of weather over a long period of time (of the order of several decades), that is, climate is the average weather. Thus, the weather is an instantaneous state of some characteristics (temperature, humidity, Atmosphere pressure). The deviation of the weather from the climatic norm cannot be considered as climate change, for example, a very cold winter does not indicate a cooling of the climate. To detect climate change, a significant trend in the characteristics of the atmosphere over a long period of time of the order of ten years is needed. The main global geophysical cyclical processes that form the climatic conditions on Earth are heat circulation, moisture circulation and general circulation of the atmosphere.

Apart from general concept"climate" has the following meanings:

• free atmosphere climate - studied by aeroclimatology.
• Microclimate
• Macroclimate - the climate of territories on a planetary scale.
• Surface air climate
• local climate
• soil climate
• phytoclimate - plant climate
• urban climate

The climate is studied by the science of climatology. Climate change in the past is studied by paleoclimatology.

In addition to the Earth, the concept of "climate" can refer to other celestial bodies (planets, their satellites and asteroids) that have an atmosphere.

Climatic zones and climate types

Climatic zones and climate types vary significantly in latitude, ranging from equatorial zone and ending with the polar, but climatic zones are not the only factor, the proximity of the sea, the atmospheric circulation system and the height above sea level also have an important influence.

In Russia and on the territory former USSR the classification of climate types, created in 1956 by the famous Soviet climatologist B.P. Alisov, was used. This classification takes into account the features of atmospheric circulation. According to this classification, four main climatic zones are distinguished for each hemisphere of the Earth: equatorial, tropical, temperate and polar (in the northern hemisphere - arctic, in the southern hemisphere - antarctic). Between the main zones there are transitional belts - subequatorial belt, subtropical, subpolar (subarctic and subantarctic). In these climatic zones, in accordance with the prevailing circulation of air masses, four types of climate can be distinguished: continental, oceanic, the climate of the western and the climate of the eastern coasts.

equatorial belt

Equatorial climate - a climate where winds are weak, temperature fluctuations are small (24-28 ° C at sea level), and precipitation is very plentiful (from 1.5 thousand to 5 thousand mm per year) and falls evenly throughout the year.

subequatorial belt

• Tropical monsoon climate - here in summer, instead of the easterly trade winds between the tropics and the equator, the westward air transfer (summer monsoon) occurs, bringing most of the precipitation. On average, they fall almost as much as in the equatorial climate. On the slopes of the mountains facing the summer monsoon, precipitation is the greatest for the respective regions, the warmest month, as a rule, occurs immediately before the onset of the summer monsoon. Characteristic for some areas of the tropics (Equatorial Africa, South and Southeast Asia, Northern Australia). In East Africa and Southwest Asia, the highest average annual temperatures on Earth (30-32 ° C) are also observed.
• Monsoon climate on tropical plateaus

tropical belt

• Tropical dry climate
• Tropical humid climate

subtropical belt

• mediterranean climate
• Subtropical continental climate
• Subtropical monsoon climate
• Climate of high subtropical highlands
• Subtropical climate of the oceans

Temperate zone

• temperate maritime climate
• temperate continental climate
• temperate continental climate
• Moderate sharply continental climate
• temperate monsoon climate

subpolar belt

• subarctic climate
• subantarctic climate

Polar belt: Polar climate

• arctic climate
• Antarctic climate

The classification of climates proposed by the Russian scientist W. Köppen (1846-1940) is widespread in the world. It is based on the temperature regime and the degree of moisture. According to this classification, eight climatic zones with eleven types of climate are distinguished. Each type has precise parameters for temperature values, the amount of winter and summer precipitation.

Also in climatology, the following concepts related to climate characteristics are used:

• Continental climate - “a climate that is formed under the influence of large land masses on the atmosphere; distributed in the interior of the continents. It is characterized by large daily and annual air temperature amplitudes.
• Maritime climate is “the climate that is formed under the influence of oceanic spaces on the atmosphere. It is most pronounced over the oceans, but also extends to areas of the continents that are subject to frequent influences of sea air masses.
• Mountain climates - "climatic conditions in mountainous areas." The main reason for the difference between the climate of the mountains and the climate of the plains is the increase in altitude. In addition, important features are created by the nature of the terrain (degree of dissection, relative height and direction of mountain ranges, exposure of slopes, width and orientation of valleys), glaciers and firn fields exert their influence. Distinguish between the actual mountain climate at altitudes of less than 3000-4000 m and high mountain climate at high altitudes.
• Arid climate - "climate of deserts and semi-deserts". Large daily and annual air temperature amplitudes are observed here; almost complete absence or insignificant amount of precipitation (100-150 mm per year). The resulting moisture evaporates very quickly.
• Humid climate - a climate with excessive moisture, in which solar heat comes in quantities insufficient to evaporate all the moisture coming in the form of precipitation.
• Nival climate - "a climate where there is more solid precipitation than can melt and evaporate." As a result, glaciers are formed and snowfields are preserved.
• Solar climate (radiation climate) - the theoretically calculated receipt and distribution of solar radiation over the globe (without taking into account local climate-forming factors.
• Monsoon climate - a climate in which the cause of the change of seasons is a change in the direction of the monsoon. As a rule, in a monsoon climate, summers are abundant in precipitation and very dry winters. Only in the eastern part of the Mediterranean, where the summer direction of the monsoons is from land, and the winter direction is from the sea, the main amount of precipitation falls in winter.
• trade wind climate

Brief description of the climates of Russia:

• Arctic: January t −24…-30, summer t +2…+5. Precipitation - 200-300 mm.
• Subarctic: (up to 60 degrees N). summer t +4…+12. Precipitation 200-400 mm.
• Moderately continental: January t -4 ... -20, July t +12 ... +24. Precipitation 500-800 mm.
• Continental climate: January t −15…-25, July t +15…+26. Precipitation 200-600 mm.
• Sharply continental: January t -25 ... -45, July t +16 ... +20. Precipitation - more than 500 mm.
• Monsoon: January t −15…-30, July t +10…+20. Precipitation 600-800. mm

Study Methods

Long-term records of meteorological observations are needed to identify climate features, both typical and rarely observed. In temperate latitudes, 25-50-year series are used; in the tropics, their duration may be shorter.

Climatic characteristics are statistical findings from long-term weather records, primarily over the following main meteorological elements: atmospheric pressure, wind speed and direction, air temperature and humidity, cloudiness and precipitation. The duration of solar radiation, visibility range, temperature are also taken into account. upper layers soil and water bodies, evaporation of water from the earth's surface into the atmosphere, the height and condition of the snow cover, various atmospheric phenomena and ground-based hydrometeors (dew, ice, fog, thunderstorms, snowstorms, etc.). In the 20th century, climatic indicators included characteristics of the elements of the heat balance of the earth's surface, such as total solar radiation, radiation balance, heat exchange between earth's surface and the atmosphere, the cost of heat for evaporation.

Long-term average values ​​of meteorological elements (annual, seasonal, monthly, daily, etc.), their sums, frequencies, and others are called climatic norms; the corresponding values ​​for individual days, months, years, etc. are considered as a deviation from these norms. To characterize the climate, complex indicators are also used, that is, functions of several elements: various coefficients, factors, indices (for example, continentality, aridity, moisture), etc.

Special climate indicators are used in applied branches of climatology (for example, sums of temperatures of the growing season in agroclimatology, effective temperatures in bioclimatology and technical climatology, degree days in calculations of heating systems, etc.).

To assess future climate changes, models of the general circulation of the atmosphere are used.

climate-forming factors

The climate of the planet depends on a whole range of external and internal factors. Most external factors affect the total amount of solar radiation received by the planet, as well as its distribution over seasons, hemispheres and continents.

External factors

Earth orbit and axis parameters

• The distance between the Earth and the Sun - determines the amount of solar energy received by the Earth.
• The inclination of the Earth's axis of rotation to the plane of the orbit - determines seasonal changes.
• The eccentricity of the Earth's orbit - affects the distribution of heat between the Northern and Southern hemispheres, as well as seasonal changes.

Milankovitch cycles - in the course of its history, the planet Earth quite regularly changes the eccentricity of its orbit, as well as the direction and angle of its axis. These changes are called "Milankovitch cycles". There are 4 Milankovitch cycles:

• Precession - rotation of the earth's axis under the influence of the attraction of the moon, and also (to a lesser extent) the sun. As Newton found out in his Elements, the oblateness of the Earth at the poles leads to the fact that the attraction of external bodies turns the Earth's axis, which describes a cone with a period (according to modern data) of approximately 25,776 years, as a result of which the seasonal amplitude of the solar flux intensity changes by northern and southern hemispheres of the Earth;
• Nutation - long-term (so-called secular) fluctuations in the angle of inclination of the earth's axis to the plane of its orbit with a period of about 41,000 years;
• Long-term fluctuations in the eccentricity of the Earth's orbit with a period of about 93,000 years.
• Movement of the perihelion of the Earth's orbit and the ascending node of the orbit with a period of 10 and 26 thousand years, respectively.

Since the described effects are periodic with a non-multiple period, fairly long epochs regularly occur when they have a cumulative effect, reinforcing each other. Milankovitch cycles are commonly used to explain the Holocene climate optimum;

• Solar activity with 11-year, secular and thousand-year cycles;
• Incident angle difference sun rays at different latitudes, which affects the degree of heating of the surface and, consequently, the air;
• The speed of rotation of the Earth practically does not change, it is a constantly acting factor. Due to the rotation of the Earth, there are trade winds and monsoons, and cyclones are also formed.
• Falling asteroids;
• The ebb and flow is caused by the action of the moon.

Internal factors

• The configuration and relative position of the oceans and continents - the appearance of a continent in the polar latitudes can lead to ice cover, and the withdrawal of a significant amount of water from the daily cycle, and the formation of supercontinents Pangea has always been accompanied by a general aridization of the climate, often against the background of glaciation, and the location of the continents also has big influence on the system of ocean currents;
• Volcanic eruptions can cause short-term climate change, up to a volcanic winter;
• The albedo of the earth's atmosphere and surface affects the amount of reflected sunlight;
• Air masses (depending on the properties of air masses, the seasonality of precipitation and the state of the troposphere is determined);
• The influence of the oceans and seas (if the area is remote from the seas and oceans, then the continentality of the climate increases. The presence of a number of oceans softens the climate of the area, with the exception of the presence of cold currents);
• The nature of the underlying surface (relief, landscape features, the presence and condition of ice sheets);
• Human activities (fuel combustion, emission of various gases, agricultural activities, deforestation, urbanization);
• Heat flows of the planet.

Atmospheric circulation

The general circulation of the atmosphere is a set of large-scale air currents above the earth's surface. In the troposphere, they include the trade winds, monsoons, as well as the transfer of air masses associated with cyclones and anticyclones. Atmospheric circulation exists due to the uneven distribution of atmospheric pressure, caused by the fact that at different latitudes of the Earth, its surface is heated differently by the sun and the earth's surface has different physical properties, especially because of its division into land and sea. As a result of the exchange of heat between the earth's surface and the atmosphere due to the uneven distribution of heat, there is a constant circulation of the atmosphere. The energy of the circulation of the atmosphere is constantly spent on friction, but is continuously replenished due to solar radiation. In the most heated places, the heated air has a lower density and rises, thus forming a zone of low atmospheric pressure. Similarly, a zone of high pressure is formed in colder places. The movement of air occurs from a zone of high atmospheric pressure to a zone of low atmospheric pressure. Since the area is located closer to the equator and farther from the poles, the better it warms up, in the lower layers of the atmosphere there is a predominant movement of air from the poles to the equator. However, the Earth also rotates on its axis, so the Coriolis force acts on the moving air and deflects this movement to the west. In the upper layers of the troposphere, a reverse movement of air masses is formed: from the equator to the poles. Its Coriolis force constantly deflects to the east, and the farther, the more. And in areas around 30 degrees north and south latitude, movement becomes directed from west to east parallel to the equator. As a result, the air that has fallen into these latitudes has nowhere to go at such a height, and it sinks down to the ground. This is where the highest pressure area is formed. Thus trade winds are formed - constant winds, blowing towards the equator and to the west, and since the wrapping force acts constantly, when approaching the equator, the trade winds blow almost parallel to it. The air currents of the upper layers, directed from the equator to the tropics, are called antitrade winds. The trade winds and anti-trade winds, as it were, form an air wheel, along which a continuous circulation of air is maintained between the equator and the tropics. During the year, this zone shifts from the equator to the warmer summer hemisphere. As a result, in some places, especially in the Indian Ocean basin, where the main direction of air transport in winter is from west to east, in summer it is replaced by the opposite one. Such air transfers are called tropical monsoons. Cyclonic activity connects the tropical circulation zone with the circulation in temperate latitudes, and between them there is an exchange of warm and cold air. As a result of interlatitudinal air exchange, heat is transferred from low to high latitudes and cold from high to low latitudes, which leads to the preservation of thermal equilibrium on Earth.

In fact, the circulation of the atmosphere is constantly changing, as due to seasonal changes in the distribution of heat on the earth's surface and in the atmosphere, and because of the formation and movement of cyclones and anticyclones in the atmosphere. Cyclones and anticyclones move generally towards the east, while cyclones deviate towards the poles, and anticyclones - away from the poles.

Thus are formed:

high pressure zones:

• on both sides of the equator at latitudes of about 35 degrees;
• in the region of the poles at latitudes above 65 degrees.

low pressure zones:

• equatorial depression - along the equator;
• subpolar depressions - in subpolar latitudes.

This pressure distribution corresponds to western transport in temperate latitudes and eastern transport in tropical and high latitudes. In the Southern Hemisphere, the zonality of atmospheric circulation is better expressed than in the Northern Hemisphere, since there are mainly oceans. The wind in the trade winds varies little, and these changes change little the nature of the circulation. But sometimes (on average, about 80 times a year) in some areas of the intratropical convergence zone (“an intermediate zone of approximately several hundred km wide between the trade winds of the Northern and Southern hemispheres”), the strongest eddies develop - tropical cyclones (tropical hurricanes), which sharply, even catastrophically, they change the established circulation regime and the weather on their way in the tropics, and sometimes even beyond them. In extratropical latitudes, cyclones are less intense than tropical ones. The development and passage of cyclones and anticyclones is an everyday phenomenon. The meridional components of the atmospheric circulation associated with cyclonic activity in extratropical latitudes change rapidly and frequently. However, it happens that for several days and sometimes even weeks, extensive and high cyclones and anticyclones hardly change their position. Then, oppositely directed long-term meridional air transfers occur, sometimes in the entire thickness of the troposphere, which propagate over large areas and even over the entire hemisphere. Therefore, in extratropical latitudes, two main types of circulation are distinguished over the hemisphere or its large sector: zonal, with a predominance of zonal, most often western, transport, and meridional, with adjacent air transports towards low and high latitudes. The meridional type of circulation carries out a much greater interlatitudinal heat transfer than the zonal one.

Atmospheric circulation also ensures the distribution of moisture both between climatic zones and within them. The abundance of precipitation in the equatorial belt is provided not only by its own high evaporation, but also by the transfer of moisture (due to the general circulation of the atmosphere) from the tropical and subequatorial belts. IN subequatorial belt atmospheric circulation ensures the change of seasons. When the monsoon blows from the sea, it rains heavily. When the monsoon blows from the dry land, the dry season begins. The tropical belt is drier than the equatorial and subequatorial belts, since the general circulation of the atmosphere carries moisture to the equator. In addition, winds from east to west prevail, therefore, due to moisture evaporated from the surface of the seas and oceans, in eastern parts continents get a lot of rain. Further west, there is not enough rain, the climate becomes arid. This is how entire belts of deserts are formed, such as the Sahara or the deserts of Australia.

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Typical for a given region of the Earth, as if the average weather for many years. The term "climate" was introduced into scientific circulation 2200 years ago by the ancient Greek astronomer Hipparchus and means in Greek "tilt" ("klimatos"). The scientist had in mind the inclination of the earth's surface to the sun's rays, the difference of which was already considered then main reason weather differences in . Later, the climate was called the average state in a certain region of the Earth, which is characterized by features that are practically unchanged for one generation, that is, about 30-40 years. These features include the amplitude of temperature fluctuations, .

Distinguish macroclimate and microclimate:

macroclimate(Greek makros - large) - the climate of the largest territories, this is the climate of the Earth as a whole, as well as large regions of land and water areas of the oceans or seas. In the macroclimate, the level and patterns of atmospheric circulation are determined;

Microclimate(Greek mikros - small) - part of the local climate. The microclimate mainly depends on differences in soils, spring and autumn frosts, the timing of snow and ice melting on water bodies. Accounting for the microclimate is essential for the placement of crops, for the construction of cities, laying roads, for any human economic activity, as well as for human health.

The description of the climate is compiled from observations of the weather over many years. It includes average long-term indicators and the number by months, frequency various types weather. But the description of the climate will be incomplete if it does not give deviations from the average. Typically, the description includes information about the highest and most low temperatures, about the largest and smallest amount of precipitation for the entire time of observations.

It changes not only in space, but also in time. A huge number of facts on this issue are given by paleoclimatology - the science of ancient climates. Studies have shown that the geological past of the Earth is the alternation of the eras of the seas and the eras of the land. This alternation is associated with slow oscillations, during which the area of ​​\u200b\u200bthe ocean either decreased or increased. In the era of increasing area, the sun's rays are absorbed by water and heat the Earth, from which the atmosphere also heats up. General warming will inevitably cause the spread of heat-loving plants and animals. Spreading warm climate The "eternal spring" in the era of the sea is also explained by an increase in the concentration of CO2, which causes the phenomenon. Thanks to him, the warming increases.

With the onset of the land era, the picture changes. This is due to the fact that land, unlike water, reflects the sun's rays more, which means it heats up less. This leads to less heating of the atmosphere, and inevitably the climate will become colder.

Many scientists consider space to be one of the important causes of the Earth. For example, fairly strong evidence of solar-terrestrial relationships is given. With an increase in the activity of the Sun, changes in solar radiation are associated, and the frequency increases. A decrease in solar activity can lead to droughts.

INTRODUCTION

The issue of climate change has attracted the attention of many

researchers whose work was mainly devoted to the collection and

studying climate data different eras. Research

of this direction contain extensive materials on the climates of the past.

Fewer results were obtained when studying the causes of changes

climate, although these reasons have long been of interest to specialists working in

this area. Due to the lack of an accurate theory of climate and the lack of

materials of special observations necessary for this purpose when clarifying

causes of climate change, great difficulties have arisen that have not been overcome until

the last time. There is currently no generally accepted reason for

changes and fluctuations in climate, both for the modern era and for

geological past.

Meanwhile, the question of the mechanism of climate change is becoming increasingly

currently of great practical importance, which until recently it did not

had. It has been established that human economic activity has begun to provide

influence of global climatic conditions, and this influence is rapidly

increases. Therefore, there is a need to develop forecasting methods

climate change in order to prevent dangerous for humans

deterioration of natural conditions.

Obviously, such predictions cannot be substantiated only by empirical evidence.

information about past climate change. These materials may be

used to evaluate climatic conditions future by extrapolation

currently observed climate change. But this forecasting method is only suitable

for very limited time intervals due to the instability of factors,

influencing the climate.

To develop a reliable method for predicting the climate of the future in

conditions of the growing influence of human economic activity on

atmospheric processes require the use of the physical theory of change

climate. Meanwhile, the available numerical models of the meteorological regime

are approximate and their justifications contain significant limitations.

Obviously, empirical evidence about climate change has

Very great importance, both for constructing and for checking approximate

theories of climate change. A similar situation occurs in the study

consequences of impacts on the global climate, the implementation of which,

apparently possible in the near future.

The purpose of this work is to analyze the climates of the past,

present and future, as well as the problems of climate regulation.

To achieve this goal, we formulated the following

1. To study the climates of past eras from literary sources;

2. Get acquainted with the methods of studying and assessing the current climate and climate

future;

3. Consider forecasts and prospects for the future climate and its problems

regulation.

Monographs and other

publications of modern domestic and foreign scientists on this

problem.

PROLOGUE CLIMATES

Quaternary period

A characteristic feature of the last (Quaternary) geological

period there was a great variability of climatic conditions, especially in

temperate and high latitudes. The natural conditions of this time have been studied

in much more detail than in earlier periods, but despite

the presence of many outstanding achievements in the study of the Pleistocene, a number of important

regularities of natural processes of this time is also known

not enough. These include, in particular, the dating of epochs

cold snaps, which are associated with the growth of ice sheets on land and

oceans. In this regard, the question of the total duration of

Pleistocene feature which was the development of large glaciations.

Essential to the development of an absolute chronology

of the Quaternary period have methods of isotope analysis, among which

include radiocarbon and potassium-argon methods. The first of these

methods gives more or less reliable results only for the last 40-50

thousand years, that is, for the final phase of the Quaternary period. Second

the method is applicable for much longer time intervals. However

the accuracy of the results of its use is noticeably less than that of radiocarbon

The Pleistocene was preceded by a long cooling process, especially

noticeable in temperate and high latitudes. This process has accelerated in the last

the Tertiary period - the Pliocene, when, apparently, the first

ice sheets in the polar zones of the northern and southern hemispheres.

It follows from the paleographic data that the formation time

glaciation in Antarctica and the Arctic is at least several million years.

The area of ​​these ice sheets was initially relatively small, but

gradually there was a tendency for their spread to lower latitudes with

subsequent absence. Start time of systematic boundary fluctuations

ice sheets are difficult to determine for a number of reasons. It is usually considered that

the movement of the ice boundary began about 700 thousand years ago.

Along with this, by the era of active development of large glaciations, often

add a longer time interval - the Eopleistocene, as a result

which the duration of the Pleistocene increases to 1.8 - 2 million years.

The total number of glaciations, apparently, was quite significant,

since the main ice ages established in the last century

turned out to consist of a series of warmer and colder time intervals,

moreover, the last intervals can be considered as independent

ice ages.

The scale of glaciation of various ice ages is significantly

were different. At the same time, the opinion of a number of researchers deserves attention, that

these scales tended to increase, that is, that the glaciation at the end

Pleistocene were larger than the first Quaternary glaciations.

The last glaciation, which took place

several tens of thousands of years ago. During this period, there was a marked increase

arid climate.

Perhaps this was due to a different decrease in evaporation from the surface

oceans due to the spread sea ​​ice to lower latitudes. IN

As a result, the intensity of moisture circulation decreased, and the amount

precipitation on land, which was affected by an increase in the area of ​​​​continents due to

withdrawal of water from the oceans, consumed during the formation of the mainland,

ice cover. There is no doubt that in the era of the last glaciation

there was a huge expansion of the permafrost zone. It's glaciation

ended 10 - 15 thousand years ago, which is usually considered the end

Pleistocene and the beginning of the Holocene - the era during which natural

conditions began to influence human activities.

Causes of climate change

Peculiar climatic conditions of the Quaternary

time, apparently arose due to the content of carbon dioxide in

atmosphere and as a result of the process of moving continents and lifting them

level, which led to the partial isolation of the Arctic Ocean and

location of the Antarctic continent in polar zone southern hemisphere.

The Quaternary period was preceded by a change-driven

surface of the Earth long-term evolution of the climate in the direction of strengthening

thermal zoning, which was expressed in a decrease in air temperature

in moderate and high latitudes. In the Pliocene on climatic conditions

began to have an effect of reducing the concentration of atmospheric

carbon dioxide, which led to a decrease in the average global temperature

air by 2 - 3 degrees (in high latitudes by 3 - 5). Then

polar ice sheets appeared, the development of which led to

decrease in global mean temperature.

Apparently, compared with changes in astronomical factors,

all other causes had a lesser effect on climate fluctuations in

Quaternary time.

Pre-Quaternary

As we move away from our time, the amount of information about

climatic conditions of the past decreases, and the difficulties of interpretation

this information is increasing. The most reliable climate information

distant past we have from evidence of continuous existence on

our planet of living organisms. It is unlikely that they exist outside

limits of a narrow temperature range, from 0 to 50 degrees C, which in

our time limits the active life of most animals and

plants. On this basis, it can be assumed that the surface temperature

The earth, the lower layer of air and the upper layer of water bodies did not leave

the specified limits. Actual fluctuations average temperature surfaces

Lands for long intervals were less than the specified interval

temperatures and did not exceed a few degrees for tens of millions of years.

From this we can conclude that it is difficult to study changes

thermal regime of the Earth in the past according to empirical data, since

errors in determining the temperature, as a method of isotope analysis

composition, and by other methods now known, they usually do not

less than a few degrees.

Another difficulty in studying past climates stems from the uncertainty

the positions of the various regions in relation to the poles as a result of the movement

continents and the ability to move the poles.

Climatic conditions of the Mesozoic era and the Tertiary period

characterized by two main patterns:

1. During this time, the average air temperature near the earth

surface was significantly higher than modern, especially in

high latitudes. Accordingly, the temperature difference

there was much less air between the equator and the poles

modern;

2. During most of the time under consideration,

tendency to decrease in air temperature, especially in high

These patterns are explained by changes in the content

carbon dioxide in the atmosphere and changes in the position of the continents. More

a high concentration of carbon dioxide provided an increase in the average

air temperature by about 5 degrees compared to modern

conditions. The low level of the continents increased the intensity of the meridional

heat exchange in the oceans, which increased the air temperature in temperate and

high latitudes.

The rise in the level of the continents reduced the intensity

meridional heat transfer in the oceans and led to a constant decrease

temperatures in temperate and high latitudes.

With a general high stability of the thermal regime in

Mesozoic and Tertiary time, due to the absence polar ice, V

during relatively rare short intervals, sharp

decrease in air temperature and upper layers of water bodies. These reductions were

due to the coincidence in time of a number of volcanic eruptions of an explosive

character.

Modern climate change

Biggest climate change ever

instrumental observations began at the end of the 19th century. It was characterized

gradual increase in air temperature at all latitudes of the northern

hemisphere in all seasons of the year, with the strongest warming

occurred at high latitudes and during the cold season. warming

accelerated in the 10s of the 20th century and peaked in the 30s, when

the average air temperature in the northern hemisphere has risen by about

0.6 degrees compared to the end of the 19th century. In the 40s the process

warming was replaced by cooling, which continues to the present

time. This cooling was rather slow and has not yet reached

the magnitude of the warming that preceded it.

Although data on present-day climate change in the southern

hemispheres are less definite than those for

warming also occurred in the southern hemisphere.

In the northern hemisphere, the rise in air temperature

was accompanied by the preservation of the area of ​​polar ice, the absence of a border

permafrost to higher latitudes, advancing to the north of the border of the forest

and tundra and other changes in natural conditions.

Significant importance was noted in the era

warming change in the regime of precipitation. Amount of precipitation in a row

areas of insufficient moisture during climate warming decreased, in

especially during the cold season. This led to a decrease in river flow and

drop in the level of some closed reservoirs.

What happened in the 1930s was especially famous.

a sharp decline in the level of the Caspian Sea, due mainly to

decrease in the flow of the Volga. Along with this, in the era of warming during

inland regions of temperate latitudes of Europe, Asia and North

America has increased the frequency of droughts covering large areas.

Warming, which peaked in the 1930s,

apparently determined by an increase in the transparency of the stratosphere, which increased

the flux of solar radiation entering the troposphere (meteorological

solar constant). This led to an increase in the average planetary

air temperature at the earth's surface.

Changes in air temperature at different latitudes and in

different seasons depended on the optical depth of stratospheric aerosol and

from the movement of the boundary of polar sea ice. warming

marine retreats arctic ice led to additional, noticeable

an increase in air temperature during the cold season in high latitudes

northern hemisphere.

It seems likely that changes in transparency

stratosphere that occurred in the first half of the 20th century were associated with the regime

volcanic activity and, in particular, with a change in income in

the stratosphere of the products of volcanic eruptions, including in particular

sulphur dioxide. Although this conclusion is based on considerable material

observations, however, it is less obvious in comparison with the above

above is the main part of explaining the causes of warming.

It should be noted that this explanation applies only to

main features of climate change that occurred in the first half of the 20

century. Along with general patterns climate change process

the process was characterized by many features related to fluctuations

climate over shorter periods of time and to climate fluctuations in

certain geographic areas.

But such climate fluctuations were largely

due to changes in the circulations of the atmosphere and hydrosphere, which had in

in some cases random in nature, and in other cases were the result of

self-oscillating processes.

There is reason to believe that in the last 20-30 years

climate change has begun to depend to a certain extent on the activities

person. Although the warming of the first half of the 20th century had a certain

impact on human economic activity and was the largest

climate change over the era of instrumental observations, its scale was

insignificant compared to the climate changes that have taken place

during the Holocene, not to mention the Pleistocene, when large

glaciation.

However, studying the warming that has occurred in

the first half of the 20th century, is of great importance for elucidating the mechanism

climate change illuminated by massive data from robust instrumental

observations.

In this regard, any quantitative theory

climate change must first of all be checked against materials

relating to the warming of the first half of the 20th century.

Climate of the future

Prospects for climate change

When studying the climatic conditions of the future, one should

focus first on the changes that can occur as a result of

natural causes. These changes may be due to the following reasons:

1. Volcanic activity. From the study of modern changes

climate it follows that fluctuations in volcanic activity can

influence climatic conditions for periods of time equal to

years and decades. Perhaps also the influence of volcanism on

climate change over periods of the order of centuries and over long

time intervals;

2. Astronomical factors. Repositioning a surface

Earth's relation to the Sun creates climate change with

time scales of tens of thousands of years;

3. Composition of atmospheric air. At the end of the tertiary and

Quaternary time, had a certain influence on the climate

attention to the rate of this decrease and the corresponding

changes in air temperature, it can be concluded that the influence

natural changes in carbon dioxide content on climate

essential for time intervals over one hundred thousand years;

4. The structure of the earth's surface. Terrain change and related

them, changes in the position of the coasts of the seas and oceans can

significantly change the climatic conditions on large

spaces for periods of time, not less than hundreds of thousands

million years;

5. Solar constant. Leaving aside the question of

the existence of climate-influencing short-period

fluctuations of the solar constant, one should take into account

the possibility of slow changes in solar radiation,

due to the evolution of the sun. Also, changes can

significantly affect climatic conditions for periods not

less than a hundred million years.

Along with changes due to external

factors, climatic conditions change as a result of self-oscillatory

processes in the system atmosphere - ocean - polar ice. Also changes

refer to time periods of the order of years - decades and, possibly, also

to periods of hundreds or even thousands of years. The times listed in this list

the scale of the impact of various factors on climate change is mainly

are consistent with similar estimates by Mitchell and other authors. Now

there is a problem of predicting climate change as a result of

human activity, which differs significantly from the problem of forecasting

weather. After all, it needs to take into account the change in time

indicators of human economic activity. In this regard, the task

climate prediction contains two main elements - a forecast of the development of a series

aspects of economic activity and calculation of those climate changes that

correspond to changes in the corresponding indicators of human activity.

Possible ecological crisis

Modern human activity, as well as his

activities in the past have significantly altered the natural environment to a greater extent

parts of our planet, these changes until recently were only the sum

many local impacts on natural processes. They purchased

planetary character not as a result of man's alteration of natural

processes on a global scale, but because local impacts

spread over large areas. In other words, the change in fauna in

Europe and Asia did not affect the fauna of America, the regulation of the flow of American

rivers did not change the flow regime African rivers and so on. Only at the very

Recently, human impact on global natural

processes, the change of which can affect natural conditions all

Taking into account the trends in the development of the economic

human activities in the modern era, it has recently been expressed

suggestion that, further development of this activity may lead to

significant change environment, which will result in

a general economic crisis and a sharp decline in the population.

Among the major problems is the question of

the possibility of change under the influence of the economic activity of the global

climate of our planet. The special significance of this question lies in the fact that

such a change could have a significant impact on the economic

human activity before all other global environmental

violations.

Under certain conditions, the impact of economic

human activities on climate may in the relatively near future

lead to warming comparable to the warming of the first half of the 20th century, and

then far surpass this warming. Thus, climate change

is perhaps the first real sign of a global environmental

crisis that humanity will face with the spontaneous development of technology and

economy.

The main cause of this crisis in its first stage

there will be a redistribution of the amount of precipitation falling in different areas

the globe, with their noticeable decrease in many areas of unstable

moisture. Since these areas are the most important areas

production of cereals, changes in precipitation patterns can significantly

make it difficult to increase food yields

rapidly growing world population.

For this reason, the issue of preventing unwanted

global climate change is one of the significant environmental

problems of the present.

The problem of climate regulation

To prevent adverse climate change,

arising under the influence of human economic activity,

various activities are carried out; most widely fought against

air pollution. As a result of application in many

developed countries of various measures, including purification of the air used

industrial enterprises, vehicles, heating

air pollution in some cities. However, in many areas, pollution

air is increasing, and there is an upward trend in global

atmospheric pollution. This points to the great difficulty in preventing

an increase in the amount of anthropogenic aerosol in the atmosphere.

Even more difficult would be the tasks (which have not yet been

were set) to prevent an increase in carbon dioxide content in

atmosphere and the growth of heat released during energy conversion,

used by man. There are no simple technical means for solving these problems.

exists, except for restrictions on fuel consumption and the consumption of most

types of energy that the coming decades are incompatible with the future

technical progress.

Thus, in order to preserve existing

climatic conditions in the near future it will be necessary to use

climate control method. Obviously, if such a method exists, it

could also be used to prevent unfavorable for the people

economy of natural climate fluctuations and in the future, corresponding

the interests of mankind.

There are a number of works that deal with

various climate impact projects. One of the largest projects has

the purpose of the destruction of the Arctic ice to significantly increase the temperature

at high latitudes. In discussing this issue, a number of

studies of the relationship between the polar ice regime and general climatic conditions.

The impact of the disappearance of polar ice on the climate will be complex and not in all

relations favorable for human activity. Not everyone

the consequences of the destruction of polar ice for climate and natural conditions

different territories can now be predicted with sufficient accuracy.

Therefore, if it is possible to destroy the ice, this event

not feasible in the near future.

From other ways of influencing climatic conditions

noteworthy is the possibility of changes in atmospheric movements of a large

scale. In many cases atmospheric movements unstable, and therefore

effects on them are possible with the expenditure of a relatively small amount

Other papers mention some methods

impact on the microclimate in connection with agrometeorological tasks. To their

number include various ways protection of plants from frost, shading

plants in order to protect them from overheating and excessive evaporation of moisture,

planting forest belts and others.

Some publications mention other projects

climate impact. These include ideas for influencing some

sea ​​currents by building giant dams. But no project

of this kind does not have sufficient scientific justification, the possible influence

their implementation on the climate remains completely unclear.

Other projects include proposals to create

large reservoirs. Leaving aside the question of the feasibility

such a project, it should be noted that the associated climate change

very little has been studied.

One might think that some of the above

limited area climate impact projects will be available for

technologies of the near future, or the expediency of their implementation will

proven.

Much more difficult to implement

impacts on the global climate, that is, on the climate of the entire planet or its

a significant part.

From various sources of climate impact pathways,

seems to be the most accessible modern technology method based on

an increase in aerosol concentration in the lower stratosphere. Implementation of this

climate change aims to prevent or mitigate change

climate, which may arise in a few decades under the influence of

human economic activity. Impacts of this magnitude can be

necessary in the 21st century, when, as a result of a significant increase in production

energy can significantly increase the temperature of the lower layers of the atmosphere.

Reducing the transparency of the stratosphere in such conditions can prevent

unwanted climate change.

Conclusion

From the above materials, you can make

conclusion that in the modern era, the global climate is already to some extent

changed as a result of human activities. These changes

are mainly due to an increase in the mass of aerosol and carbon dioxide in

atmosphere.

Modern anthropogenic changes in the global climate are comparatively

small, which is partly due to the opposite effect on temperature

air growth of the concentration of aerosol and carbon dioxide. However, these

changes have a certain practical significance, mainly in connection with

influence of the rainfall regime on agricultural production. At

maintaining the current pace of economic development anthropogenic

changes can quickly increase and reach scales exceeding

the scale of natural climate fluctuations that have occurred during the last

centuries.

In the future, under these conditions, climate change

will increase, and in the 21st century they may become comparable to

natural fluctuations in climate. It is obvious that such significant

climate change can have a huge impact on the nature of our planet

and many aspects of human economic activity.

As a result, prediction problems arise.

anthropogenic climate change that will occur under various options

economic development, and development of climate regulation methods,

which should prevent it from changing in an undesirable direction.

The presence of these tasks significantly changes the meaning of change studies.

climate and especially the study of the causes of these changes. If earlier such

studies had largely educational goals, but now

the need for their implementation for optimal planning is ascertained

development of the national economy.

The international aspect of the problem should be pointed out

anthropogenic climate change, which is becoming especially large

importance in the preparation of large-scale climate impacts. Impact

on the global climate will lead to a change in climatic conditions on

territories of many countries, and the nature of these changes in different areas

will be different. In this regard, in the work of E. K. Fedorov repeatedly

It was pointed out that the implementation of any major impact project on

climate change is only possible through international cooperation.

Now there are grounds for raising the question of

imprisonment international agreement prohibiting the implementation

uncoordinated climate impacts. Such influences must be allowed

only on the basis of projects reviewed and approved by the responsible

international bodies. This agreement should cover both activities

in terms of directed impact on climate, and those types of economic

human activities that may lead to unintended

applications of global climate conditions.

Literature

Budyko M.I. Climate change. - Leningrad: Gidrometeoizdat, 1974. - 279 p.

Budyko M.I. Climate in the past and future.- Leningrad: Gidrometeoizdat, 1980.-

Losev K.S. Climate: yesterday, today... and tomorrow? - Leningrad,

Gidrometeoizdat, 1985. 173 p.

Monin A.S., Shishkov Yu.A. History of climate. - Leningrad: Gidrometeoizdat,

The Earth's climate has a large number of regularities and is formed under the influence of many factors. At the same time, it is fair to attribute to it a variety of phenomena in the atmosphere. The climatic state of our planet largely determines the state of natural environment and human activities, especially economic.

The climatic conditions of the Earth are formed by three large-scale geophysical processes of a cyclic type:

• Heat transfer- exchange of heat between the earth's surface and the atmosphere.
• moisture circulation- the intensity of water evaporation into the atmosphere and its correlation with the level of precipitation.
• General atmospheric circulation- a set of air currents over the Earth. The state of the troposphere is determined by the features of the distribution of air masses, for which cyclones and anticyclones are responsible. Atmospheric circulation occurs due to the unequal distribution of atmospheric pressure, which is due to the division of the planet into land and water bodies, as well as uneven access to ultraviolet radiation. The intensity of the sun's rays is determined not only by geographical features, but also the proximity of the ocean, the frequency of precipitation.

Climate should be distinguished from weather, which is the state of the environment at the current moment. However, weather characteristics are often the subject of climatology, or even the most important factors in changing the Earth's climate. In the development of the earth's climate, as well as weather conditions heat level plays a special role. Also, the climate is influenced by sea currents and relief features, in particular, the proximity of mountain ranges. No less important role belongs to the prevailing winds: warm or cold.

In the study of the Earth's climate, careful attention is paid to such meteorological phenomena as atmospheric pressure, relative humidity, wind parameters, temperature indicators, precipitation. They also try to take into account solar radiation in compiling a general planetary picture.

climate-forming factors

1. Astronomical factors: the brightness of the Sun, the ratio of the Sun and the Earth, the features of the orbits, the density of matter in space. These factors affect the level of solar radiation on our planet, daily weather changes, and the spread of heat between the hemispheres.
2. Geographical factors: the weight and parameters of the Earth, gravity, air components, the mass of the atmosphere, currents in the ocean, the nature of the earth's relief, sea level, etc. These features determine the level of heat received in accordance with the weather season, continent and hemisphere of the earth.

The industrial revolution led to the inclusion in the list of climate-forming factors of active human activity. However, all characteristics of the Earth's climate are largely influenced by the energy of the Sun and the angle of incidence of ultraviolet rays.

Earth climate types

There are many classifications of the planet's climatic zones. Various researchers take as the basis for the separation, both individual characteristics and the general circulation of the atmosphere or the geographical component. Most often, the basis for distinguishing a separate type of climate is the solar climate - the influx of solar radiation. The proximity of water bodies and the ratio of land to sea are also important.

The most simple classification identifies 4 basic belts in each hemisphere of the earth:

• equatorial;
• tropical;
• moderate;
• polar.

Between the main zones there are transitional sections. They have the same names, but with the prefix "sub". The first two climates, together with the transitions, can be called hot. In the equatorial region, there is a lot of precipitation. Temperate climate has more pronounced seasonal differences, especially in the case of temperature. As for the cold climate zone, these are the most severe conditions caused by the absence of solar heat and water vapor.

This division takes into account atmospheric circulation. According to the predominance of air masses, it is easier to divide the climate into oceanic, continental, and also the climate of the eastern or western coasts. Some researchers define the continental, maritime and monsoon climate additionally. Often in climatology there are descriptions of mountainous, arid, nival and humid climates.

Ozone layer

This concept refers to the layer of the stratosphere with increased level ozone, which is formed due to the influence sunlight to molecular oxygen. Due to the absorption of ultraviolet radiation by atmospheric ozone, the living world is protected from combustion and widespread cancer. Without the ozone layer, which appeared 500 million years ago, the first organisms would not have been able to get out of the water.

Since the second half of the 20th century, it has been customary to talk about the problem of the "ozone hole" - a local decrease in the concentration of ozone in the atmosphere. The main factor of such change is anthropogenic in nature. The ozone hole can lead to increased mortality of living organisms.

Global changes in the Earth's climate

(Increase in mean air temperature over the past century since the 1900s)

Large-scale climate transformations are considered by some scientists as a natural process. Others believe that this is a harbinger of a global catastrophe. Such changes mean a strong warming of the air masses, an increase in the level of aridity and a softening of winters. We are also talking about frequent hurricanes, typhoons, floods and droughts. The cause of climate change is the instability of the Sun, which leads to magnetic storms. Changes in the earth's orbit, the outlines of the oceans and continents, and volcanic eruptions also play a role. The greenhouse effect is also often associated with destructive human activities, namely: atmospheric pollution, deforestation, plowing land, burning fuel.

Global warming

(Climate change towards warming in the second half of the 20th century)

An increase in the average temperature of the Earth has been recorded since the second half of the 20th century. Scientists believe that the reason for this is the high levels of greenhouse gases due to human activity. The consequence of rising global temperatures is changing precipitation, the growth of deserts, the frequency of extreme weather events, the extinction of some biological species, and the rise in sea levels. Worst of all, in the Arctic, this leads to a decrease in glaciers. All together, this can radically change the habitat of various animals and plants, move the boundaries natural areas and cause serious problems agriculture and human immunity.